Wireless power transfer can be employed to charge a plug-in electric vehicle (PEV) without physical contact between a charging device and the PEV. Charging stations including a primary coil can be installed to provider wireless power transfer to such PEV's. A vehicle including a second coil can be placed in proximity to a primary coil of a charging device for wireless power transfer. The efficiency of wireless power transfer depends on the coupling constant between the primary coil and the secondary coil, e.g., by the percentage of the magnetic flux from the primary coil that is captured by the secondary coil. In order to reliably provide efficient wireless power transfer, it is necessary to ensure that the vehicle is aligned to the charging device including the primary coil within alignment tolerances every time the vehicle is placed in a charging position.